 All cells have  Plasma membrane – an outer boundary     Covers the cell’s surface Acts as a barrier between the inside and the outside All materials enter through the plasma membrane Made of phospholipids, proteins and cholesterol.

 All cells have  Cytoplasm     Within the plasma membrane Includes fluid, cytoskeleton, and organelles Cytosol is the liquid Made up of water and proteins

 All Cells Have  DNA     Controls what goes on in the cell Tells the cell what proteins to make Copies itself for reproduction Made of Nucleotides

  There are two basic types of cells Prokaryotes  Organisms that are unicellular      Do not have a membrane bound nucleus Do not have membrane bound organelles Even though they do not have a nucleus they still have DNA in the center region called the nucleoid.

Bacteria and Archaea May be the first life forms

 Eukaryotes  Organisms made up of one or more cells that have a nucleus.

    Have many membrane bound organelles Organelles carry out different functions Much larger than prokaryotes Include Animal Cells, Plant Cells, Fungi, Protists

 Phospholipid Bilayer  Two layers of phospholipids    Phospholipids have a hydrophilic head and a hydrophobic tail Makes the membrane fluid Makes the membrane semi permeable

 Cholesterol  a lipid that makes the membrane firm  Prevents the membrane from freezing at low temperatures

 Membrane Proteins  Glycoproteins – identifies other cells receives signals   Integral Proteins out of the cell.

– span from one side of he membrane to the other, transport materials into and Peripheral proteins – enzymes that speed up (catalyze) reactions in the cell

    Most functions are controlled by the nucleus Filled with nucleoplasm Contains genetic information which codes the structure and function of the organ Made of DNA & proteins

   The nucleus is the site where DNA is transcribed into RNA which moves through nuclear pores to the cytoplasm The nuclear envelope surrounds the nucleus.

Made of phospholipids and proteins Nuclear Pore

    Most nuclei contain one or more denser/darker areas Is the site where ribosomes are made Ribosomes make proteins in the cell Made of dense DNA Nucleolus

    Tiny organelles that transfer energy from organic molecules (like sugar) to ATP ATP is the energy that the cell uses to function. Has its own DNA Can reproduce by fission like bacteria.

  Cells that are very active like muscle cells have a lot of mitochondria Cells that are not active like fat storage cells do not have a lot of mitochondria.

  Outer membrane – smooth and completely permeable to nutrient molecules, ions, ATP and ADP molecules. Inner membrane – has many folds and proteins that aid in the production of ATP, the energy rich molecules.

  Cristae – the infolds of the inner membrane Matrix – the space in between the folds. Has a mixture of enzymes that are important for the synthesis of ATP molecules, special mitochondrial ribosomes, and DNA

 Due to their independence from the nuclear DNA and similarities with bacteria, it is believed that mitochondria have originated from bacteria by endosymbiosis .

   Ribosomes are the sites of protein synthesis.

Occur in both prokaryotes and eukaryotes.

Are found floating around the cytoplasm or attached to the endoplasmic reticulum and in the mitochondria.

  Tiny organelles composed of both proteins and RNA Each subunit consists of one or two very large RNA molecules (known as ribosomal RNA) and several smaller protein molecules.

   Abbreviated ER is the system of membranous tubes that run throughout the cell from the nucleus to the cell membrane Functions as an intercellular highway, a path through which molecules move from one part of the cell to another.

Two types  Rough ER  Smooth ER

    Covered with ribosomes Produces phospholipids proteins and Proteins are made on the surface by the ribosomes and then ER.

imported into the cell or the cell membrane by the rough There is a lot of rough ER in cells that produce lots of proteins like the pancreas and white blood cells.

      Does not have ribosomes on the surface Most cells have a small amount of smooth ER Builds lipids like cholesterol, testosterone, estrogen, Releases calcium Abundant in liver cells and the kidney cells The more alcohol & drug abuse, the more smooth ER.

     Also called Golgi Body or just Golgi Flattened membranous sacs Found in all eukaryotic cells Functions as a packaging and distribution center The sacs nearest the nucleus receive vesicles from the ER containing newly made proteins and lipids.

  As the vesicles move along inside of the Golgi, the contents are modified, they get address label to be sent somewhere in the cell.

The modified proteins and lipids leave out of the other side of the golgi.

    Small sacs that move substances through the cell and to the membrane to be released from the cell.

Lysosomes – contain digestive enzymes that digest bacteria and dead cell parts.

Peroxisomes – neutralize free radicals like hydrogen peroxide.

Glyoxysomes – break down stored fats in seeds

   Endosomes – engulf materials to take to the lysosomes to digest Food Vacuoles – store nutrients for the cell Contractile vacuoles – expel excess water from the cell.

Contractile Vacuoles

    Hairlike organelles that extend from the surface of cells.

Found on many eukaryotic cells.

Cilia are mostly found on animal cells They assist in movement .

   Short and hairlike Found in thousands on the surface of cells.

Help unicellular organisms move through water to find food.

  Also found on cells lining the respiratory tract.

Trap particles and debris from the air we inhale.

  Longer and less numerous than cilia A cell could have one flagella (sperm) or many.

  Structure are the same for cilia and flagella.

They are composed of 9 pairs of microtubules arranged around a central pair.

   Only found in plant cells and fungi.

Rigid and made of cellulose in plants and chitin in fungi Helps to support and protect the cell membrane.

     Only found in plant cells Trap sunlight to create sugar/ food for the plant cell.

Flattened membranes called thylakoids enclosed in a membrane Contain a green pigment called chlorophyll.

Give plants their color

   Are like mitochondria in that they contain their own DNA and ribosomes.

They are surrounded by a double membrane.

They can reproduce themselves inside of the plant cell.

     The shapes of cells vary.

Some, such as nerve cells are being longer than they are wide.

Parenchyma (a common type of plant cell) and Red blood cells being equal on all sides.

Some cells are encased in a rigid wall, which confines their shape.

Some have a flexible cell membrane (and no rigid cell wall).

Amoeba Red Blood Cells

   The size of cells is also related to their functions.

Eggs are very large, often being the largest cells an organism produces.

Cells range in size from small bacteria to large, unfertilized eggs laid by birds and dinosaurs.